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In2O3 films were epitaxially grown on (0001)α-Al2O3 substrates by mist CVD, and the impact of hydrochloric acid (HCl) was investigated by varying the HCl concentration in the source solution. Single-phase rhombohedral corundum-type In2O3 films, without the incorporation of body-centered cubic bixbite-type In2O3 phases, could be successfully grown directly on α-Al2O3 substrates by controlling only the HCl concentration. In growth by mist CVD, adding HCl to the source solution was found to affect not only the dissolution of the source precursor but also the growth kinetics of phase control, surface migration and impurity incorporation. [ABSTRACT FROM AUTHOR]

ALMA cycle 3 observations of 12CO J = 3 → 2, 13CO J = 4 → 3, SiO J = 8 → 7, and HCN J = 5 → 4 are presented. Significant extended emission is detected in 12CO J = 3 → 2 with a morphology that is indicative of m = 2 tidal features, suggesting gas inflow. In addition, outflows for both nuclei are found in 12CO J = 3 → 2. Significant SiO absorption is detected in the western nucleus. HCN that is morphologically distinct from CO is detected in both nuclei. These observations are compared to non-LTE radiative transfer models created using the Line Modeling Engine for simple gas dynamics to gain insight into how physical parameters, such as rotational velocity, turbulent velocity, gas temperature, dust temperature, and gas mass, can reproduce the observed kinematic and spatial features. The eastern nucleus is found to be best modeled with an inclusion of a temperature asymmetry from one side of the disk to the other. It is also found that the western nucleus is optically thick even in the less abundant species of 13CO, absorbing significant amounts of continuum radiation. [ABSTRACT FROM AUTHOR]

We review the binding and energy level alignment of π-conjugated systems on metals, a field which during the last two decades has seen tremendous progress both in terms of experimental characterization as well as in the depth of theoretical understanding. Precise measurements of vertical adsorption distances and the electronic structure together with ab initio calculations have shown that most of the molecular systems have to be considered as intermediate cases between weak physisorption and strong chemisorption. In this regime, the subtle interplay of different effects such as covalent bonding, charge transfer, electrostatic and van der Waals interactions yields a complex situation with different adsorption mechanisms. In order to establish a better understanding of the binding and the electronic level alignment of π-conjugated molecules on metals, we provide an up-to-date overview of the literature, explain the fundamental concepts as well as the experimental techniques and discuss typical case studies. Thereby, we relate the geometric with the electronic structure in a consistent picture and cover the entire range from weak to strong coupling. [ABSTRACT FROM AUTHOR]

We systematically investigate the electrical and magnetic properties of n-type ferromagnetic semiconductor (In,Fe)As thin films grown on vicinal GaAs(001) substrates with different lattice-relaxation layers and Fe-doping techniques. We show that spinodal decomposition and ferromagnetism can be enhanced in the (In,Fe)As thin films grown on InAs lattice-relaxation layers under the nucleation growth mode, while they are suppressed in those grown on the GaSb/AlSb/AlAs (from top to bottom) lattice-relaxation layers under the step-flow growth mode. We demonstrate that room-temperature ferromagnetism and good electrical properties can be obtained at the same time by using the Fe-delta-doping technique in combination with the step-flow growth mode. [ABSTRACT FROM AUTHOR]

The installation of a phase adjuster (PA) has been proposed to improve the cooling effect of loop-tube-type thermoacoustic cooling systems. Installing a PA in a circular tube is equivalent to reducing the tube diameter locally. In this paper, we report our numerical investigation of the effects of the configuration parameters of a PA, i.e., diameter reduction and installation position, on the critical temperature of thermoacoustic gas oscillations by utilizing the transfer matrix method. The PA was modeled considering reflections due to the impedance mismatch at the boundaries between different diameters. The calculation results indicate that the critical temperature significantly decreases when a certain level of diameter reduction at appropriate positions is set, and these results correspond to empirical configurations that were experimentally chosen and verified in past studies. [ABSTRACT FROM AUTHOR]

We have studied the power reduction rate and degradation modes of crystalline-silicon photovoltaic modules, which had been operated in an outdoor field for about 10 years. We measured the electric parameters of the modules before and after 10-year operation, and classified our photovoltaic modules into four groups that were manufactured by four manufacturers. Analyzing the age-related decreases in electric parameters of the modules, we found two dominant degradation modes by correlation analysis of the electric parameters. In addition, we found delamination mode degradation by visual inspection. We have recognized a degradation rate in terms of the statistical distribution of the module power reduction. The power reduction rate was found to be an average of 4.7% for ten years. [ABSTRACT FROM AUTHOR]

Thermoacoustic systems have several advantages owing to their simple structure driven by heat energy such as waste heat and solar heat. However, because their energy conversion efficiency is low, they have not been developed for practical use. Therefore, to improve energy conversion efficiency, a method of system design development is examined in this report using numerical calculations. First, calculation results obtained using the transfer-matrix methods are compared with experimentally obtained results, which confirms their good agreement. Secondly, calculated results of each heat flow element in the stack show that heat flow proportional to the temperature gradient QD, which decreases the performance of the system, is dominant. Finally, the installation position of the stack is changed to reduce the ratio that QD occupies in the heat flow. Results show a decrease in the ratio obtained by moving the stack installation position closer to the center of the tube. Energy conversion efficiency was increased eight times. [ABSTRACT FROM AUTHOR]

In this report, we propose a loop-tube-type thermoacoustic system with a diverging sub-loop tube to control the sound field, specifically the phase difference between sound pressure and particle velocity, in the prime mover of a thermoacoustic system for improvement in energy conversion. The phase difference must become 0° or near 0°. This phase difference contributes to energy conversion through isothermal heat exchange process and makes a thermoacoustic system highly efficient in terms of energy conversion. The sub-loop tube diverges from the main loop tube and rejoins it. Thereby, the sub-loop tube forms a loop. The sub-loop tube position is changed. By diverging the sub-loop tube, the acoustic impedance at the connection position changes and the resonance condition in the thermoacoustic system is changed. As a result, the phase difference in the prime mover is controlled for improvement in energy conversion. Nevertheless, the phase difference in the prime mover cannot be measured. The sound field and ωτ are measured with and without a sub-loop tube. The degree of heat exchange between the working gas and the stack wall is represented as ωτ, which is the product of angular frequency ω and thermal relaxation time τ. Results show that diverging the sub-loop tube and changing its position alter the sound field in the thermoacoustic system, specifically changing the phase difference in the prime mover. The change in the phase difference in the prime mover raises the efficiency of energy conversion from heat to sound. [ABSTRACT FROM AUTHOR]

The finite element method (FEM) is applied to the analysis of the steady-state sound field in a thermoacoustic tube in the frequency domain. Although the thermoacoustic field is nonlinear and isothermal, a linear and adiabatic model is proposed, in which only the sound intensity field is considered because the sound intensity is generally discussed for the efficiency of energy conversion in the thermoacoustic system. In the numerical model, the divergence of the sound intensity is modeled as the sound source and the dissipation is modeled as loss caused by the specific acoustic impedance of the wall. Some numerical demonstrations are made for the two-dimensional standing wave field in a straight tube with a lossy wall. The influences of the stack and the phase adjuster on the sound field are examined. It is found that the sound field in the thermoacoustic tube can be qualitatively analyzed by introducing the specific acoustic impedance of the wall. [ABSTRACT FROM AUTHOR]

The structure of the stack in the prime mover, the energy conversion part from heat energy to sound energy, is examined to improve the thermoacoustic cooling performance of the loop tube cooling system. In this system, the stack is the most important device. When the heat flux gradient within it is increased, the strong sound intensity is realized. The metallic materials are attached on top of the honeycomb ceramic stack as the active areas for the heat source to improve the energy conversion from heat energy to sound energy. Because of the high heat conductivity of the metallic material, copper is used for experiments described in this report. Compared with that of the ceramic, the increased heat flux is realized by multiplying the heat conductivity and the temperature gradient. Results confirmed that the amount of heat flux in the stack increases with the use of metallic materials. Experimental results show that the efficiency of the energy conversion almost doubles using the presented structure of the stack. [ABSTRACT FROM AUTHOR]

Experimental investigations were performed to miniaturize a loop-tube cooling system. The parameter ωτ is regarded as a dimensionless parameter expressing the efficiency of the system's heat exchange. This parameter is related to the sound generation efficiency and depends on the frequency, stack channel radius and temperature. Both the resonance frequency of the generated sound and ωτ are affected by the total loop-tube length. However, the value of ωτ can also be controlled by changing the stack channel radius or temperature. Experiments were carried out changing the total loop-tube length under the same constant value of ωτ. Experimental results confirmed that similar heat exchange efficiencies are obtained when the loop-tube configuration is changed. Therefore, the heat exchange efficiency of the miniature loop-tube can be estimated using large loop-tubes with the same value of ωτ. Consequently, ωτ is a useful and important parameter for designing a miniature loop-tube cooling system. [ABSTRACT FROM AUTHOR]

The use of a phase adjuster (PA) is proposed to reduce the temperature difference between the upper and lower ends of the prime mover stack in a loop-tube-type thermoacoustic cooling system. PA is a device for increasing particle velocity. By placing PA in the loop tube, the resonance is forcibly one wavelength. It is confirmed that the temperature difference of the prime mover stack with PA is smaller than that without PA. Because PA prevents the resonance wavelength shift from one-wavelength resonance to two-wavelength resonance, the loop tube suppresses the increase in temperature at the prime mover stack, so that the viscous boundary layer thickness is smaller than the stack channel radius. This induces an effective energy conversion. Consequently, the temperature difference is reduced. [ABSTRACT FROM AUTHOR]

SmB6, a topological Kondo insulator, with a gapped bulk state and metallic surface state has aroused great research interest. Here, we report an exotic hysteresis behavior of magnetoresistance in individual SmB6 nanowire in a temperature range in which both surface and bulk states contribute to the total conductance. Under a magnetic field parallel to the SmB6 nanowire, the resistance suddenly increases at the turning point from up-sweep to down-sweep of the magnetic field. The magnetoresistance hysteresis loops are well consistent with the magnetocaloric effect. Our results suggest that the SmB6 nanowires possess potential applications in the magnetic cooling technology. [ABSTRACT FROM AUTHOR]

This paper proposes an application of a general purpose graphic processing unit (GPGPU) to the finite element method analysis based on the hierarchical cascading technique (HCT). It is proved that GPGPU can accelerate the HCT significantly, especially for large scale problems. Thanks to significant acceleration, full three-dimensional simulation is possible for practical surface acoustic wave (SAW) device structures. Besides admittance curve, the displacement field is calculated. It is shown that SAW scattering occurs at the boundary at busbar spaces between the interdigital transducer (IDT) and reflector regions. [ABSTRACT FROM AUTHOR]

Reactions for dissociative ionization and neutral dissociation collisions between an electron and a tetraethoxysilane [Si(OC2H5)4, TEOS] molecule are reported, and neutral dissociation cross sections are calculated by applying the classical Rice–Ramsperger–Kassel theory. Detailed electron collision cross section set of TEOS vapor, including 18 neutral dissociation cross sections and 20 ionization cross sections, is constructed. Electron transport coefficients, such as the mean-arrival-time drift velocity, bulk drift velocity, longitudinal bulk diffusion coefficient, and ionization coefficient, and rate coefficients for both elastic and inelastic collisions in TEOS vapor are calculated from the present cross section set using a Monte Carlo method. The validity of the present cross section set is demonstrated by comparing the calculated electron transport coefficients with measured data. Furthermore, fragmentation of TEOS molecules by electron impact is simulated, and then the number of fragments produced in the simulation is compared with the measured mass spectra. [ABSTRACT FROM AUTHOR]

A novel diamond anvil cell specialized for resistivity measurements under high pressure have been developed. Boron-doped metallic diamond electrodes were deposited onto a nano-polycrystalline diamond anvil using a microwave plasma-assisted chemical vapor deposition technique combined with electron beam lithography. The various designs of boron-doped metallic diamond electrodes were demonstrated, and they showed no signs of degradation after repeated compression. [ABSTRACT FROM AUTHOR]

We studied a thermoacoustic cooling system driven at low temperatures to make practical use of the system. Aiming to reduce the driving temperature of the thermoacoustic system, we developed a loop-tube-type thermoacoustic system with diameter-expanded two-stage prime movers, i.e., a heat-to-sound transducer. The system drove at 67 °C. Additionally, we developed a prototype for a thermoacoustic cooling system with a diameter-expanded two-stage prime mover. In the experiment, the cooling point temperature was decreased by 4.4 °C from room temperature, i.e., 20 °C. To improve the cooling performance of the prototype thermoacoustic cooling system, we experimentally investigated the effect of increasing the input power on the cooling performance. [ABSTRACT FROM AUTHOR]

Reducing the driving temperature of a thermoacoustic system to effectively utilize the unused low-temperature heat source is important for improving the performance of the system. The driving temperature of the thermoacoustic system was reduced by installing multiple stages of prime movers in series, a heat-to-sound transducer, and a prime mover with an increased cross-sectional area. In this study, the oscillation temperature was investigated both experimentally and by stability analysis in order to verify whether the system is operable, and to determine its operating temperature, when changing the installation position of the two-stage prime mover with increased cross-sectional area. [ABSTRACT FROM AUTHOR]

Since the Infrared Space Observatory (ISO) mission, it has become clear that dust in circumstellar disks and outflows consists partly of crystalline silicates of pyroxene and olivine type. An exact mineralogical analysis of the dust infrared emission spectra relies on laboratory spectra, which, however, have been mostly measured at room temperature so far. Given that infrared spectral features depend on the thermal excitation of the crystal's vibrational modes, laboratory spectrameasured at various (low and high) temperatures, corresponding to the thermal conditions at different distances from the star, can improve the accuracy of such analyses considerably.We have measured the complex refractive index in a temperature range of 10-973K for one mineral of each of those types of silicate, i.e., for an olivine and an enstatite of typical (terrestrial) composition. Thus, our data extend the temperature range of previous data to higher values and the compositional range to higher iron contents. We analyze the temperature dependence of oscillator frequencies and damping parameters governing the spectral characteristics of the bands and calculate absorption cross-sectional spectra that can be compared with astronomical emission spectra. We demonstrate the usefulness of our new data by comparing spectra calculated for a 100K dust temperature with the ISO SWS spectrum of IRAS 09425-6040. [ABSTRACT FROM AUTHOR]

A simple and low-cost method for improving organic light-emitting diode (OLED) performance by printing poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT : PSS) grids on the anode is demonstrated. The PEDOT : PSS grids were printed by an aerosol jet printer on the ITO anode surface. The maximum current efficiency of the OLED modified with the PEDOT : PSS grids is 1.92 times higher than a conventional device. The power efficiency enhancement factor is 2.3 at the current density of 740 mA cm−2. The enhancement in performance can be attributed to the light extraction and conductivity of the embedded low-index grids. [ABSTRACT FROM AUTHOR]

We present optical, near-infrared, and radio observations of the afterglow of GRB 120521C. By modeling the multi-wavelength data set, we derive a photometric redshift of z ≈ 6.0, which we confirm with a low signal-to-noise ratio spectrum of the afterglow. We find that a model with a constant-density environment provides a good fit to the afterglow data, with an inferred density of n ≲ 0.05 cm–3. The radio observations reveal the presence of a jet break at tjet ≈ 7 d, corresponding to a jet opening angle of θjet ≈ 3°. The beaming-corrected γ-ray and kinetic energies are Eγ ≈ EK ≈ 3 × 1050 erg. We quantify the uncertainties in our results using a detailed Markov Chain Monte Carlo analysis, which allows us to uncover degeneracies between the physical parameters of the explosion. To compare GRB 120521C to other high-redshift bursts in a uniform manner we re-fit all available afterglow data for the two other bursts at z ≳ 6 with radio detections (GRBs 050904 and 090423). We find a jet break at tjet ≈ 15 d for GRB 090423, in contrast to previous work. Based on these three events, we find that γ-ray bursts (GRBs) at z ≳ 6 appear to explode in constant-density environments, and exhibit a wide range of energies and densities that span the range inferred for lower redshift bursts. On the other hand, we find a hint for narrower jets in the z ≳ 6 bursts, potentially indicating a larger true event rate at these redshifts. Overall, our results indicate that long GRBs share a common progenitor population at least to z ∼ 8. [ABSTRACT FROM AUTHOR]

We propose a neonization method to deal with molecules composed by hydrides of the second row of the periodic table of elements: CH4, NH3, OH2 and FH. This method describes these ten-electron molecules as dressed atoms in a pseudo-spherical potential. We test it by covering most of the inelastic collisional magnitudes of experimental interest: ionization cross sections (total, single and double differential), stopping power, energy-loss straggling and mean excitation energy. To this end, the neonization method has been treated with different collisional formalisms, such as the continuum-distorted-wave–eikonal-initial-state, the first order Born, and the shell-wise local plasma approximations. We show that the present model reproduces the different empirical values with high reliability in the intermediate to high-energy region. We also include the expansion of the spherical wave functions in terms of Slater-type orbitals and the analytic expression for the spherical potentials. This makes it possible in the future to tackle present neonization strategy with other collisional models. [ABSTRACT FROM AUTHOR]

We present new Spectrographic Areal Unit for Research on Optical Nebulae (SAURON) integral-field spectroscopy and Swift Ultraviolet Optical Telescope (UVOT) observations of molecular outflow host galaxy NGC 1266 that indicate NGC 1266 has experienced a rapid cessation of star formation. Both the SAURON maps of stellar population age and the Swift UVOT observations demonstrate the presence of young (<1 Gyr) stellar populations within the central 1 kpc, while existing Combined Array for Research in Millimeter-Wave Astronomy CO(1-0) maps indicate that the sites of current star formation are constrained to only the inner few hundred parsecs of the galaxy. The optical spectrum of NGC 1266 from Moustakas & Kennicutt reveal a characteristic poststarburst (K+A) stellar population, and Davis et al. confirm that ionized gas emission in the system originate from a shock. Galaxies with K+A spectra and shock-like ionized gas line ratios may comprise an important, overlooked segment of the poststarburst population, containing exactly those objects in which the active galactic nucleus (AGN) is actively expelling the star-forming material. While AGN activity is not the likely driver of the poststarburst event that occurred 500 Myr ago, the faint spiral structure seen in the Hubble Space Telescope Wide-field Camera 3 Y-, J- and H-band imaging seems to point to the possibility of gravitational torques being the culprit. If the molecular gas were driven into the center at the same time as the larger scale galaxy disk underwent quenching, the AGN might be able to sustain the presence of molecular gas for ≳ 1 Gyr by cyclically injecting turbulent energy into the dense molecular gas via a radio jet, inhibiting star formation. [ABSTRACT FROM AUTHOR]